Plastic bowling pin for bowling alleys



Aug. 25, 1970 A. SCHMID 3,525,524

PLASTIC BOWLING PIN FOR BOWLING ALLEYS Filed Jan. 6. 196'? AUGUST SC/lM/D INVENTOR United States Patent 3,525,524 PLASTIC BOWLING PIN FOR BOWLING ALLEYS August Schmid, Schwerzenbach, Switzerland, assignor to Serania AG. Patentverwertungsund Finanzierungsgesellschaft, Glarus, Glarus, Switzerland, a corporation of Switzerland Filed Jan. 6, 1967, Ser. No. 607,739 Claims priority, applicatitzglstivgitzerland, Jan. 12, 1966,

Int. Cl. A63b 9/00 US. Cl. 273-82' 8 Claims ABSTRACT OF THE DISCLOSURE A bowling pin formed of plastic and-incorporating a specially configured base portion to which is molded by use of an undercut portion the body portion of the bowling pin in a manner preventing detachment of the body portion and base portion from one another. Since the base portion is formed of a plastic material which is extremely wear resistant, the longevity of the bowling pin is insured, and the manner of attachment of said base portion with the body portion is so secure that there is little or no likelihood of separation of such members from one another. The base portion contains a housing which mounts a spring-biassed ball. The base portion is preferably of nylon and the body portion is preferably of polyethylene.

BACKGROUND OF THE INVENTION The present invention has reference to an improved bowling pin for bowling alleys and the like and which is formed of a synthetic material, typically plastic, and incorporates an inserted base portion.

It has been found with plastic bowling pins that, during bowling, the lower portion of the base of the pin is subjectced to pronounced wear and that this portion, as a practical matter, determines the longevity of the bowling pin. It has already been proposed to reinforce the base of the bowling pin by a ring inserted in an axial groove. However, in actual practice it was soon found that such rings are subjected to impacts during bowling which they are'unable to cope with, and consequently, after a short period of playing use, these rings become loose and fall out.

Furthermore, it has already been attempted to threadably attach or secure said reinforcement rings, yet this solution once again was not satisfactory since the relatively long screw means also had the tendency of becoming loosened after a short time when subjected to impacts and vibrations.

SUMMARY OF THE INVENTION Accordingly, it is a primary object of the present in vention to provide an improved bowling pin which effectively overcomes the abovementioned drawbacks of the prior art structures.

Another, more specifice object of the present invention has reference to an improved bowling pin which utilizes a bowling pin base which is as wear resistant as possible, and further, this base is connected with the remaining portion of the bowling pin in such a manner that the connectcion is faultlessl ymaintained and positively insured during the entire periodd of use or life of the bowling pin.

Generally speaking, the plastic bowling pin of the invention incorporates at least a body portion and a base portion inserted at said body portion. According to a very important aspect of the invention, this base portion advantageously includes means providing an undercut region, to thereby connect by molding the material of the 3,525,524 Patented Aug. 25, 1970 body portion with the base portion in an undetachable manner.

BRIEF DESRIPTION OF THE DRAWING The invention will be better understood, and objects other than those set forth above, will become apparent, when consideration is given to the following detailed description thereof and showing, by way of example, two embodiments of inventive bowling pin. Such description of these embodiments makes reference to the annexed drawing wherein:

FIG. 1 is a fragmentary, cross-sectional view through the lower portion of a bowling pin according to a first embodiment of the invention; and

FIG. 2 is a fragmentary, cross-sectional view through the lower portion of a second embodiment of inventive bowling pin.

Describing now the drawing and, more particularly, making reference to the exemplar embodiment of bowl ing pin depicted in FIG. 1, it should be recognized that this bowling pin 1, intended-to be used for bowling, possesses a form or shape which is conventional for such pins. More specifically, the depicted bowling pin 1 has a base portion 2, a body portion or belly 20, a non-illustrated neck portion and a non-illustrated head portion. Usually, the body portion 20 has integrally formed thereon the neck portion and head portion. The depicted bowling pin 1 cannot only be used for so-called cableless bowling installations such as are commonly found here in the United States, but also, can be provided at the head of the bowling pin with a cable or like pulling member, as such is quite usual in European bowling alleys.

Bowling pin 1 is formed of a suitable plastic and is either solid walled or manufactured from a foamable plastic wherein only the core or center portion has gas inclusions. As already remarked, this bowling pin 1 is provided at its lower region with a base portion 2, likewise formed of a suitable plastic, and which with regard to the plastic of the upper portion or body 20 of the pin, continuing, it will be recognized that the base portion 2 is provided with a floor or base surface 8 forming the actual support surface for this bowling pin 1.

A spring housing 3, also formed of a suitable plastic, is inserted approximately at the central or middle region of the base portion 2. This spring housing 3 is centrally provided with a downwardly projecting pin or plug member 4 serving as guide means for the helical spring member 5. The lower end of the spring member 5 presses against a ball or sphere 6 situated in a central opening 21 of the pin base portion 2. This central opening or bore 21 advantageously possesses a diameter which is somewhat smaller than the diameter of the associated ball or sphere member 6, so that the latter is resiliently retained in the base portion 2. Further, it will be recognized that this base portion 2 is provided with means forming an undercut region, herein the form of the circumferential groove means 7. The upper portion 10' of the base portion 2 and bounding the circumferential groove means 7 at the top advantageously possesses a smaller diameter than the lower portion 23 of this base portion 2 and bounding said circumferential groove means at the bottom. Furthermore, this upper portion 10 of the base portion 2 is provided with a rounded-off region 9. Also, it will be recognized that base portion 2 is centrally provided with a suitable recess 24 into which there is seated the aforementioned spring housing 3.

The depth a of the circumferential groove means 7 at least corresponds to the wall thickness b between the rounded-off region 9 and the confronting outer surface 25 of the bowling pin 1. Further, the width or height 0 of this circumferential groove means 7 corresponds to approximately the depth a of the aforesaid circumferential groove means. Additionally, it will be appreciated that the base portion 2 provides a flush extension or continuation at the parting location or plane 12, that is free of projections or shoulders, with the body portion 20 of the bowling pin 1 located thereabove. Consequently, the lower region of the base portion 2 extends up to the outer surface 2-5 of the bowling pin and at its outer region therefore forms a portion of the surface of such bowling pin.

- Owing to the physical construction previously described, it will be recognized that the plastic material of the bowling pin 1 therefore extends into the circumferential groove means 7, and consequently, in this manner encloses the base portion 2 in an undetachable manner, because the material which extends into the aforesaid groove means 7 forms together with the remaining bowling pin material a single plastic piece produced by injection molding techniques. Since, considering the fact that the spring housing 3 and associated components mounted at the base portion 2 are, in effect one piece or component, it will be appreciated that the remainder of the bowling pin in this embodiment consists of a further component which is formed of a single piece and which extends above the aforesaid base portion 2. The body portion 20' of the bowling pin '1 is preferably formed of polyethylene, whereas a polyamide (nylon) has proven itself to be advantageous as the material for the pin base portion 2. It is here also mentioned that the depth a and width or height of the circumferential groove means 7 each amount to at least about of the diameter of the base surface 8.

Turning now to the variant form of inventive bowling pin depicted in FIG. 2, wherein like reference numerals have once again been employed for the same or analogous elements, it will be seen that this bowling pin 1 is of the type that is not equipped with any ball or sphere member 6. In order that space is provided for any eventual, retractable centering pin, the bowling pin base portion 2 is here provided with a downwardly opening centering bore 13 having at its open end a countersunk portion 14. The standing or base surface 8 of the base portion 2 is provided at its central region with a flat, retracted recess 17. Moreover, with regard to the circumferential groove means 7, the same data is also here applicable which was given with regard to the embodiment of FIG. 1. The groove depth a amounts to about A3 to A of the diameter d of the base surface 8. This is also true with regard to the width or height 0 of such groove means 7.

It is also conceivable. to form the portion of the bowling pin 1 located above the base portion 2 of two parts or components, namely, a core portion 18 and a jacket portion 19, wherein the parting plane is indicated by the broken lines 16. Thus, in this embodiment, the material of the jacket 19 extends into the groove means 7 and, therefore, insures for a positive anchoring of the base portion 2 with the remaining portion of the bowling pin 1.

It should be apparent from the foregoing detailed description, that the objects set forth at the outset to the specification have been successfully achieved. The foregoing detailed description has been given for clearness of understanding only, and no unnecessary limitations should be understood therefrom, as modifications will be obvious to those skilled in the art. Accordingly, what is claimed is:

'1. A bowling pin formed of plastic for use with bowling alleys, said bowling pin incorporating at least a body portion and a base portion inserted at said body portion, said base portion including means providing at least one undercut region, said body portion being molded in one piece to thereby enclose said undercut region of said base portion in an undetachable manner, said pin having an open housing retained in a displacement-proof manner therein with part of said base portion underlying said housing to partially enclose same, said housing communicating at one end thereof with the exterior of said pin by means of an opening in said base portion.

2. A bowling pin formed of plastic for use with bowling alleys, said bowling pin incorporating at least a body portion and a base portion joined to said body portion, said base portion including means providing at least one undercut region having an upper portion and a lower portion and defining a circumferential groove of given depth and width, said body portion being molded about and enclosing said undercut region of said base portion in an undetachable manner, the thickness of said body portion disposed between said upper portion of said undercut region and the outer surface of said body portion being substantially equal to said given depth and width of said circumferential groove.

3. A bowling pin as defined in claim 2, wherein said body portion and said base portion are constructed of respectively different plastics.

4. A bowling pin as defined in claim 2, wherein said inserted base portion includes a lower portion which is configured to provide a flush extension of the surface of the body portion of the bowling pin.

'5. A bowling pin as defined in claim 2, wherein said bowling pin only consists of two parts, and the part of the bowling pin disposed above said base portion is formed of a single piece.

6. A bowling pin as defined in claim 2, wherein said body portion includes a core and a jacket, said jacket being molded to said base portion.

7. A bowling pin as defined in claim 2, wherein said base portion includes a base surface and an upper portion axially spaced therefrom, said circumferential groove means being disposed between said base surface and said upper portion.

8. A bowling pin as defined in claim 7, wherein said base surface possesses a greater diameter than said upper portion.

References Cited UNITED STATES PATENTS 1,705,280 3/1929 Blair 27 3- 82 2,517,116 8/1950 Klinger 273-82 2,701,719 2/ 1955 DiPierro 273-82 2,738,977 3/ 1956 Riley 273-82 3,232,616 2/ 1966 Conklin 273-82 3,329,430 7/ 1967 Wanders 273-82 2,814,835 12/1957 Faulkner 27382 FOREIGN PATENTS 25 3,036 11/1948 Switzerland.

1 218,496 1 1/ 1928- Switzerland.

3949081 12/ 1965 Switzerland.

344,939 4/ 1960 Switzerland.

ANTON O. OECHSLE, Primary Examiner R. W. DIAZ, Assistant Examiner 

